5 files changed, 112 insertions, 27 deletions

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 110aeeb52f9..96c92191046 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -1,2 +1,5 @@
 config CLKSRC_I8253
 	bool
+
+config CLKSRC_MMIO
+	bool
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index cfb6383b543..b995942a506 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_SH_TIMER_CMT)	+= sh_cmt.o
 obj-$(CONFIG_SH_TIMER_MTU2)	+= sh_mtu2.o
 obj-$(CONFIG_SH_TIMER_TMU)	+= sh_tmu.o
 obj-$(CONFIG_CLKSRC_I8253)	+= i8253.o
+obj-$(CONFIG_CLKSRC_MMIO)	+= mmio.o
diff --git a/drivers/clocksource/mmio.c b/drivers/clocksource/mmio.c
new file mode 100644
index 00000000000..c0e25125a55
--- /dev/null
+++ b/drivers/clocksource/mmio.c
@@ -0,0 +1,73 @@
+/*
+ * Generic MMIO clocksource support
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/clocksource.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+
+struct clocksource_mmio {
+	void __iomem *reg;
+	struct clocksource clksrc;
+};
+
+static inline struct clocksource_mmio *to_mmio_clksrc(struct clocksource *c)
+{
+	return container_of(c, struct clocksource_mmio, clksrc);
+}
+
+cycle_t clocksource_mmio_readl_up(struct clocksource *c)
+{
+	return readl_relaxed(to_mmio_clksrc(c)->reg);
+}
+
+cycle_t clocksource_mmio_readl_down(struct clocksource *c)
+{
+	return ~readl_relaxed(to_mmio_clksrc(c)->reg);
+}
+
+cycle_t clocksource_mmio_readw_up(struct clocksource *c)
+{
+	return readw_relaxed(to_mmio_clksrc(c)->reg);
+}
+
+cycle_t clocksource_mmio_readw_down(struct clocksource *c)
+{
+	return ~(unsigned)readw_relaxed(to_mmio_clksrc(c)->reg);
+}
+
+/**
+ * clocksource_mmio_init - Initialize a simple mmio based clocksource
+ * @base:	Virtual address of the clock readout register
+ * @name:	Name of the clocksource
+ * @hz:		Frequency of the clocksource in Hz
+ * @rating:	Rating of the clocksource
+ * @bits:	Number of valid bits
+ * @read:	One of clocksource_mmio_read*() above
+ */
+int __init clocksource_mmio_init(void __iomem *base, const char *name,
+	unsigned long hz, int rating, unsigned bits,
+	cycle_t (*read)(struct clocksource *))
+{
+	struct clocksource_mmio *cs;
+
+	if (bits > 32 || bits < 16)
+		return -EINVAL;
+
+	cs = kzalloc(sizeof(struct clocksource_mmio), GFP_KERNEL);
+	if (!cs)
+		return -ENOMEM;
+
+	cs->reg = base;
+	cs->clksrc.name = name;
+	cs->clksrc.rating = rating;
+	cs->clksrc.read = read;
+	cs->clksrc.mask = CLOCKSOURCE_MASK(bits);
+	cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+
+	return clocksource_register_hz(&cs->clksrc, hz);
+}
diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index f975d24890f..036e5865eb4 100644
--- a/drivers/clocksource/sh_cmt.c
+++ b/drivers/clocksource/sh_cmt.c
@@ -24,6 +24,7 @@
 #include <linux/ioport.h>
 #include <linux/io.h>
 #include <linux/clk.h>
+#include <linux/pm_runtime.h>
 #include <linux/irq.h>
 #include <linux/err.h>
 #include <linux/clocksource.h>
@@ -152,10 +153,12 @@ static int sh_cmt_enable(struct sh_cmt_priv *p, unsigned long *rate)
 {
 	int ret;
 
-	/* enable clock */
+	/* wake up device and enable clock */
+	pm_runtime_get_sync(&p->pdev->dev);
 	ret = clk_enable(p->clk);
 	if (ret) {
 		dev_err(&p->pdev->dev, "cannot enable clock\n");
+		pm_runtime_put_sync(&p->pdev->dev);
 		return ret;
 	}
 
@@ -187,8 +190,9 @@ static void sh_cmt_disable(struct sh_cmt_priv *p)
 	/* disable interrupts in CMT block */
 	sh_cmt_write(p, CMCSR, 0);
 
-	/* stop clock */
+	/* stop clock and mark device as idle */
 	clk_disable(p->clk);
+	pm_runtime_put_sync(&p->pdev->dev);
 }
 
 /* private flags */
@@ -416,11 +420,15 @@ static cycle_t sh_cmt_clocksource_read(struct clocksource *cs)
 
 static int sh_cmt_clocksource_enable(struct clocksource *cs)
 {
+	int ret;
 	struct sh_cmt_priv *p = cs_to_sh_cmt(cs);
 
 	p->total_cycles = 0;
 
-	return sh_cmt_start(p, FLAG_CLOCKSOURCE);
+	ret = sh_cmt_start(p, FLAG_CLOCKSOURCE);
+	if (!ret)
+		__clocksource_updatefreq_hz(cs, p->rate);
+	return ret;
 }
 
 static void sh_cmt_clocksource_disable(struct clocksource *cs)
@@ -448,19 +456,10 @@ static int sh_cmt_register_clocksource(struct sh_cmt_priv *p,
 	cs->mask = CLOCKSOURCE_MASK(sizeof(unsigned long) * 8);
 	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
 
-	/* clk_get_rate() needs an enabled clock */
-	clk_enable(p->clk);
-	p->rate = clk_get_rate(p->clk) / ((p->width == 16) ? 512 : 8);
-	clk_disable(p->clk);
-
-	/* TODO: calculate good shift from rate and counter bit width */
-	cs->shift = 0;
-	cs->mult = clocksource_hz2mult(p->rate, cs->shift);
-
 	dev_info(&p->pdev->dev, "used as clock source\n");
 
-	clocksource_register(cs);
-
+	/* Register with dummy 1 Hz value, gets updated in ->enable() */
+	clocksource_register_hz(cs, 1);
 	return 0;
 }
 
@@ -665,6 +664,7 @@ static int __devinit sh_cmt_probe(struct platform_device *pdev)
 
 	if (p) {
 		dev_info(&pdev->dev, "kept as earlytimer\n");
+		pm_runtime_enable(&pdev->dev);
 		return 0;
 	}
 
@@ -679,6 +679,9 @@ static int __devinit sh_cmt_probe(struct platform_device *pdev)
 		kfree(p);
 		platform_set_drvdata(pdev, NULL);
 	}
+
+	if (!is_early_platform_device(pdev))
+		pm_runtime_enable(&pdev->dev);
 	return ret;
 }
 
diff --git a/drivers/clocksource/sh_tmu.c b/drivers/clocksource/sh_tmu.c
index 36aba992306..17296288a20 100644
--- a/drivers/clocksource/sh_tmu.c
+++ b/drivers/clocksource/sh_tmu.c
@@ -25,6 +25,7 @@
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/clk.h>
+#include <linux/pm_runtime.h>
 #include <linux/irq.h>
 #include <linux/err.h>
 #include <linux/clocksource.h>
@@ -109,10 +110,12 @@ static int sh_tmu_enable(struct sh_tmu_priv *p)
 {
 	int ret;
 
-	/* enable clock */
+	/* wake up device and enable clock */
+	pm_runtime_get_sync(&p->pdev->dev);
 	ret = clk_enable(p->clk);
 	if (ret) {
 		dev_err(&p->pdev->dev, "cannot enable clock\n");
+		pm_runtime_put_sync(&p->pdev->dev);
 		return ret;
 	}
 
@@ -141,8 +144,9 @@ static void sh_tmu_disable(struct sh_tmu_priv *p)
 	/* disable interrupts in TMU block */
 	sh_tmu_write(p, TCR, 0x0000);
 
-	/* stop clock */
+	/* stop clock and mark device as idle */
 	clk_disable(p->clk);
+	pm_runtime_put_sync(&p->pdev->dev);
 }
 
 static void sh_tmu_set_next(struct sh_tmu_priv *p, unsigned long delta,
@@ -199,8 +203,12 @@ static cycle_t sh_tmu_clocksource_read(struct clocksource *cs)
 static int sh_tmu_clocksource_enable(struct clocksource *cs)
 {
 	struct sh_tmu_priv *p = cs_to_sh_tmu(cs);
+	int ret;
 
-	return sh_tmu_enable(p);
+	ret = sh_tmu_enable(p);
+	if (!ret)
+		__clocksource_updatefreq_hz(cs, p->rate);
+	return ret;
 }
 
 static void sh_tmu_clocksource_disable(struct clocksource *cs)
@@ -221,17 +229,10 @@ static int sh_tmu_register_clocksource(struct sh_tmu_priv *p,
 	cs->mask = CLOCKSOURCE_MASK(32);
 	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
 
-	/* clk_get_rate() needs an enabled clock */
-	clk_enable(p->clk);
-	/* channel will be configured at parent clock / 4 */
-	p->rate = clk_get_rate(p->clk) / 4;
-	clk_disable(p->clk);
-	/* TODO: calculate good shift from rate and counter bit width */
-	cs->shift = 10;
-	cs->mult = clocksource_hz2mult(p->rate, cs->shift);
-
 	dev_info(&p->pdev->dev, "used as clock source\n");
-	clocksource_register(cs);
+
+	/* Register with dummy 1 Hz value, gets updated in ->enable() */
+	clocksource_register_hz(cs, 1);
 	return 0;
 }
 
@@ -414,6 +415,7 @@ static int __devinit sh_tmu_probe(struct platform_device *pdev)
 
 	if (p) {
 		dev_info(&pdev->dev, "kept as earlytimer\n");
+		pm_runtime_enable(&pdev->dev);
 		return 0;
 	}
 
@@ -428,6 +430,9 @@ static int __devinit sh_tmu_probe(struct platform_device *pdev)
 		kfree(p);
 		platform_set_drvdata(pdev, NULL);
 	}
+
+	if (!is_early_platform_device(pdev))
+		pm_runtime_enable(&pdev->dev);
 	return ret;
 }